To the Chinese, the US double standard is obvious. The harshest words from the State Department seem to come from spokeswoman Marie Harf on Dec 30, 2013, when she called on Uygurs to not resort to violence, but she also urged the Chinese government to permit its citizens to express their grievances freely, publicly, peacefully and without fear of retribution and she called on Chinese security forces to exercise restraint.

On every other occasion, Harf's answers, often read from a thick pile of prepared notes in front of her, are that the US is still trying to gather all the facts before making its evaluation, even months after the attack. Harf has not said the US condemned the attacks or expressed condolences over the dead.

Yet on the same day of Dec 30, Harf said the US condemns in the strongest terms the terrorist attacks in Volgograd, Russia, which killed civilians and policeman, without saying whether the US had gathered all the facts of the attack.

To the Chinese, such double standards also included last week's transfer of three Uygur detainees, all Chinese citizens, from the Guantanamo military detention center to Slovakia, despite Chinese request that they should be repatriated back to China.

Harf did not answer the question whether the US should be held responsible if these detainees, plus another 19 transferred to various destinations in previous years, conduct terrorist activities against civilians later. In Guantanamo, the US had kept 22 Uygur militants caught in combat zones in Afghanistan and Pakistan. Many of them had received training in Taliban camps.

To some, the US' war on terrorism is only to serve its own interests. "The US released the three Uygurs and transferred them to Slovakia because 'they do not pose threat to the US'. This is very shaky excuse. Uygur radicals do not attack American police or kill American civilians, but they do pose a security threat inside China," said Zhu Zhiqun, professor of political science and international relations at Bucknell University.

The ETIM, which has a track record of carrying out terrorist activities, was designated in 2002 by both the US and the UN as a terrorist group associated with Osama bin Laden and his al-Qaida network. The US State Department later took it off the Foreign Terrorist Organization list.

"Terrorism may take different forms or result from different situations, but all kinds of violence is inexcusable and must be stopped," Zhu said.

"As the global leader in the anti-terror campaign, the US should be consistent and condemn all terrorist acts and work with other countries to curb terrorism globally."

Contact the writer at chenweihua@chinadailyusa.com.